Improvement in slate and blackboard rubbers



6.1. HIGGINS.

81313 and Black-Board Rubbers. w 'g g'f' v Patented March17,'1874.

mMm-umabw/m' cm tram/ms mmw CHARLES J. HIGGINS, OF INDIANAPOLIS,INDIANA.

lMPROVEMENT IN SLATE AND BLACKBOARD RUBBERS.

Epecification forming part of Letters Patent No. 148,393, dated March17, 1874; application filed November 29, 1873.

To all whom it may concern.

Be it known that I, CHARLES J. HIGGINS, of Indianapolis, Marion county,State of Indiana, have invented an Improved Eraser or Rubber for ErasingMarks from Blackboards or Slates, of which the following is aspecification: 7

The obj eet of my invention is to provide an eraser or rubber forremoving marks from blackboards and slates, in which the severalportions of a continuous or endless band of cloth or other suitablematerial may be used successively, until the entire band is foul or wornout, when, by the peculiar construction of the blocks on which the clothor other suitable material is supported, it may be readily removed forcleansing or renewal. My invention consists in the construction andcombination of the various parts, as hereinafter more fully described. 7

Figure 1, A is a peculiarly-shaped block of wood or other suitablematerial, designed to serve as a support for the erasing-surface. Fig. 2shows the block A surrounded with a loosely-fitting band, 0, of cloth orother suitable material, for erasing marks on a blackboard or slate.Fig. 3, B is a strip or block of wood or other suitable material,designed to serve as a clamp for pressing the bandOclosely around theblock A, and also to serve as a handle for the device. Fig. 4 shows thevarious parts of my device in their proper place, ready for use.

The construction of the blocks A and B is such that when placed togetherin proper position for use, the 'band C is drawn snugly around the blockA, and kept firmly in place. This is accomplished by forming grooves inone block and corresponding projections in the other, so that whenplaced together portions of the band C are pressed into the grooves, andthe band thus drawn tightly and held firmly.

I do not confine myself to the particular forms of projections andgrooves here shown, as they may be made straight or in other suitableforms, so that they act when interlocked to hold in place and tightenthe band 0 upon its supporting-block.

The operation of my device is as follows: The endless band 0 having beenplaced around the block A, it is pressed into the grooves in the sidesof the block A until the upper portion of the block and its coveringwill enter the dovetail-shaped groove in the block B, which is thenslipped forward until the ends of the blocks are even, thus clamping theband 0 snugly and securely to its place. When that portion of the bandwhich is exposed for use becomes foul or worn, it is only necessary todraw ofi' the block B, slip the band 0 around on the block A until a newportion is brought opposite the broad portion of A, when, the blockBbeing replaced, the eraser is again ready for use.

It is obvious that when the entire surface of the band has been used itmay be readily removed, and a new one substituted at' a slight expense.

I claim as my invention- 1. In combination with the endless band (3, theblocks A and B, when provided with one or more interlocking projectionsand grooves, substantially as shown and described, and for the purposeset forth.

2. In combination with the blocks A and B, the endless band (1, whenmade removable from said blocks and adjustable, substantially in themanner described, and for the purpose set forth.

CHAS. J. HIGGINS.

